A power miter saw is a cutting tool used to make crosscuts in a work piece, such as a piece of wood. Miter saws typically include a base equipped with a turntable and fence. The turntable is rotatable in relation to the base and has an upper surface that supports a work piece during cutting operations. The fence extends over the turntable to provide an abutment surface for locating an edge of the work piece at a predetermined position on the base.
The saw assembly of the miter saw includes a bevel arm, a cutting arm, and a cutting assembly. The bevel arm is pivotably attached to the turntable for pivotal movement about a bevel axis. The cutting arm is in turn pivotably attached to the bevel arm for pivotal movement toward and away from the turntable. The cutting arm supports the cutting assembly, comprising a circular saw blade and a motor, above the turntable. During cutting operations, the cutting arm is pivoted downwardly to bring the saw blade into contact with a work piece positioned on the turntable.
Miter saws have a cut capacity that defines the maximum sizes and dimensions of work pieces that a miter saw is capable of cutting through. The cut capacity includes a vertical component, also referred to as the cut height capacity, and a horizontal component, also referred to as the cut width capacity. The cut height and cut width capacity of a miter saw depend on a number of factors, such as the size of the saw blade, the depth that the blade is able to plunge below the upper surface of the turntable, the pivot location of the support arm with respect to the abutment surface of the fence, and the size of the motor, gearbox, and blade arbor.
The cut height capacity of a miter saw may have to be adjusted to accommodate taller work piece sizes. One method used to increase the cut height capacity of a miter saw is to attach a sacrificial fence to the front of the fence. FIGS. 8 and 9 depict the cut width and cut height capacity of a miter saw before and after attaching a sacrificial fence to the miter saw fence. As depicted in FIG. 8, the miter saw has a cut width capacity of 190 mm, and a cut height capacity of 88 mm. As depicted in FIG. 8, the sacrificial fence has a thickness on the front of the fence of approximately 20 mm that results in an increase in cut height capacity to 102 mm and a decrease in cut width capacity to 150 mm. The use of the sacrificial fence allows the miter saw to have a cut capacity capable of cutting a 100 mm×100 mm cross section beam.
While effective in increasing cut height capacity, the use of sacrificial fences requires that time be spent selecting and/or fabricating a fence with a desired width and suitable shape for attachment to the miter saw fence. Time must also be spent in the installation and removal of the sacrificial fence. Because sacrificial fences are often made with scrap materials, sacrificial fences are often discarded after use requiring that another sacrificial fence be selected and/or fabricated to increase the cut height capacity of the miter saw for another job.
What is needed is a method or device that enables the cut height capacity of a miter saw to be increased without requiring the fabrication and installation of a separate sacrificial fence or spacer.